Fareed speaks with the Frederick P. Rose director of the Hayden Planetarium, astrophysicist Neil deGrasse Tyson, about the implications of the meteor that exploded over the Ural Mountains last month. To see this or other interviews, download the show at iTunes.

The laws of math are that the probability is one of these things will hit...

Globally, what deeply concerns you is the asteroid strong enough so you have to restart civilization. And then, at another level, you risk extinction. Fortunately, those are large and we have a plan in place. NASA has a plan in place to detect and map and track every single asteroid that’s large enough to disrupt civilization. The one that exploded over Russia was not large enough to disrupt civilization. And so they’re dangerous and they'll hurt and they can kill, but the fact that we can’t track them is not as bad as not being able to track the big ones that could really destroy us. So once you know where they are, your next question would be, perhaps, do we have a plan to do something about it?

And the answer is no. It's all just on paper how to do it.

What would be the plan? Would it be some kind of military...?

Yes...

You’d shoot a missile to shatter it in outer space and...

Yes, that’s the macho solution is you pull one of your missiles out of the silo that have been sitting there doing nothing since the Cold War and you blow the sucker out of the sky. The problem is, I mean, here in America, we’re really good at blowing stuff up and less good at knowing where the pieces land, you know…So, people who have studied the problem generally – and I’m in this camp – see a deflection scenario is more sound and more controllable. So if this is the asteroid and it's sort of headed toward us, one way is you send up a space ship and they'll both feel each other. And the space ship hovers. And they'll both feel each other's gravity. And they want to sort of drift toward one another. But you don't let that happen. You set off little retro rockets that prevent it. And the act of doing so slowly tugs the asteroid into a new orbit.

Because the space ship has a kind of gravitational pull...

Exactly. They want to draw toward each other, but if you don't let that happen and you constantly yank the space ship away ever so slightly, then the asteroid will chase the space ship ever so slightly. And that's all you need if you get it early enough, because the tiniest change in your orbit early can completely avoid the target. Now, of course, it's there to harm you another day. But if you get really good at this, then you can have a protection system for the Earth that will prevent humans from going extinct.

Now, is it fair to say that we don't need any innovation in physics or even in engineering? We know how to do this. The question is the will and the resources to implement a plan like that.

Yes, I mean we use ordinary physics to know how to make this work, physics and engineering, of course, because you've got to make the hardware to enable it. And the price is not even all that expensive given other activities that humans have undertaken. The problem is the asteroid that we might find that will one day hit us. You want to get it early – when do we start concerning ourselves with a budget to handle it? If it’s going to come in 100 years, what do you say? Ah, let our descendants worry about that in their Congress. You know, 88 percent of Congress faces reelection every two years…And so that's not a long enough time scale to match the time scales that matter for our survival. Plus, if an asteroid is going to strike somewhere else in the world, is it NASA that's going to take care of that? So what you really want, I think, is a world organization, maybe every country chips in, in proportion to their GDP, something sensible like that. And then there's a pot of money. And whoever has the space faring resources at the time it's necessary…would then tap into that money and then you save the Earth. And I think that's a reasonable path.

soundoff(212 Responses)

Alex

Well I would also like to comment on this dilema. I don't at all agree with the idea of blowing a meteor to smitherines in space hoping that this "solution" would help. It would only make matters much, much worse. We would have to worry about several new, but smaller meteors crashing toward Earth. I have watched several episodes on " The Universe" about this matter and have a developed understanding on the matter. Our best bet is to have a spacecraft orbit the meteor early in its path.....say 100 years in advance (provided that we have such notice). This will allow us to safely alter the overall orbit of the meteor to effectively spare the lives of human kind. We are but a seemingly rare happening when it comes to the universe. Life as we know it couldn't be more perfect. We have the perfect place in our solar system and it would be absurd to shrug this issue off our shoulders for later civilizations. The question isn't "if it will happen", rather, WHEN IT WILL HAPPEN. There seems to be a regular occurrence roughly every 20 million years. This occurrence would be a mass extinction due to impacts from something from outer space. The problem that stands as of now would be less distant impacts from meteors. We do need a plan to save our race and the simple and safe way to do this would be to redirect the path of any future meteors.

The nuclear option is by far the best, all of these other options are not practical and would take too long. We won't have 100 years, we would have 10 if we are lucky. Sending up multiple nuclear weapons to deflect the asteroid is the fastest, easiest, cheapest way. If done properly the asteroid will not fragment it will just be nudged away using the same principles as the Orion drive (Nuclear Pulsed Propulsion). The real question is detection, we need infrared space telescopes to give us a proper heads up so we can actually get a plan together, right now we don't have any.

If it happens, it happens. I don't think there's any way we can keep a colossal meteor from hitting the Earth. All we can .do is put our affairs in order and face the end as bravely as possible. The dinosaurs didn't have a choice, either.

Has a nuclear weapon ever been fired in a vacuum or in space? Do we even know all the consequences of doing something like that are yet? If the asteroid is mile or so in size, will a nuclear device even work? The asteroids are moving at 35,000 plus. Is it even practical to believe we could fire something effectively at them? Large asteroids will have debris (i.e., smaller bodies in front of them that we have no way to track or see). Missiles may hit this debris before hitting the asteroid if we plan to shot at it. Landing on the asteroid is not possible at their speeds accept in movies. Space landmine fields at multiple layers that attract to metal perhaps? It all seems very expensive and unlikely we will see international support on the level we need until it is probably too late.

The "best" solution all depends on the amount of time before impact and the exact nature and composition of the incoming object. If we have decades or centuries we would have the luxury of time to send out exploratory probes to better determine the nature and exact trajectory of the object and devise some cool elegant solution to the problem. On the other hand, if we have only a couple years time we'd have to act pretty quickly with whatever we've got on the shelf and we could just barely do that. Nukes would look like a really good solution in this scenario. If we've only got two years or less, all this talk would be academic because we'd probably just have to sit here and wait for the end, since nothing could be designed, tested, built, launched and have the time to travel the distance required to intercept the object at a safe distance from earth.

We probably will need to put in orbit a huge atomic bomb that will timely intersect the trayectory of the falling object. If we have a space station in orbit for so long, why not have a dozen atomic bombs ready to deflect the falling meteorite? I would attempt to hit it from de side at a ninety degree angle. The explosion will not destroy the object size of Apophis (900 feet diameter), but will change its trayectory by enough amount to make it pass the earth by. If one bomb fails, all dozen may need to be used.

Desert Voice – not even remotely possible. The Chelyabinsk meteor in February was travelling at something like Mach 60, roughly 11-12 miles per SECOND. There's just no way we can target ANYTHING at a 90 degree angle moving that fast at close range. No to mention that at that sort of distance from Earth you'd have better luck deflecting a Major League fastball by farting at it.

If you're trying to stop an impactor already at or close to High Earth Orbit it's already far too late.

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